89.1k views
15 votes
F(x) =3x+8 find the inverse of f(x)

User Ewan
by
7.8k points

1 Answer

9 votes

Answer:

Explanation:

Hi!

To find the inverse, first we express your function as:

y = 3x - 8

Then, we interchange x and y variables:

x = 3y - 8

From there, we isolate y:

x + 8 = 3y

x/3 + 8/3 = y

Then, the inverse, g(x) = (x+8)/3.

We can check this by getting g(f(x)):

(f(x) + 8)/3 = (3x - 8 + 8)/3 = 3x /3 = x.

This is correct by the definition of the inverse function.

You can also think about the inverse as a "reverse function", so for example, in f(x) = 3x-8, x is multiplied by 3, then 8 is subtracted from it.

If we are to go from f(x) to x, we first add 8 (to reverse the subtraction), then divide by 3 (to reverse the multiplication).

This means g(y) = (y+8)/3, the same answer.

Hope this helps!

User Octavio
by
8.2k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories